Co-production of heat and power: an anchor tenant of a regional industrial ecosystem

The resource basis of industrial energy production is still, to a large extent, in non-renewable fossil fuels, the use of which creates emissions that the ecosystem has difficulty in tolerating. The goal of industrial ecology is to substitute the non-renewable stocks with renewable flows. In this paper, a regional industrial ecosystem that relies on a power plant as its key organisation, as an anchor tenant, is considered in the context of energy production and consumption. The co-production method of heat and electricity (CHP, co-production of heat and power) is implemented in the local power plant. This method uses the waste energy from electricity production for district heat and industrial heat/steam. The fuel basis in a CHP plant can include heterogeneous waste fuels. The method has been applied, to a large extent, in only three countries in the world; Denmark, The Netherlands and Finland. Examples of CHP-based industrial ecosystems from Finland are considered. CHP is reflected upon from the viewpoint of industrial ecosystem principles.     

Biomass-based negative emission technology options with combined heat and power generation

Biomass-based combined heat and power (CHP) generation with different carbon capture approaches is investigated in this study. Only direct carbon dioxide (CO₂) emissions are considered. The selected processes are (i) a circulating fluidized bed boiler for wood chips connected to an extraction/condensation steam cycle CHP plant without carbon capture; (ii) plant (i), but with post-combustion CO₂ capture; (iii) chemical looping combustion (CLC) of solid biomass connected to the steam cycle CHP plant; (iv) rotary kiln slow pyrolysis of biomass for biochar soil storage and direct combustion of volatiles supplying the steam cycle CHP plant with the CO₂ from volatiles combustion escaping to the atmosphere; (v) case (iv) with additional post-combustion CO₂ capture; and (vi) case (iv) with CLC of volatiles. Reasonable assumptions based on literature data are taken for the performance effects of the CO₂ capture systems and the six process options are compared. CO₂ compression to pipeline pressure is considered. The results show that both bioenergy with carbon capture and storage (BECCS) and biochar qualify as negative emission technologies (NETs) and that there is an energy-based performance advantage of BECCS over biochar because of the unreleased fuel energy in the biochar case. Additional aspects of biomass fuels (ash content and ash melting behavior) and sustainable soil management (nutrient cycles) for biomass production should be quantitatively considered in more detailed future assessments, as there may be certain biomass fuels, and environmental and economic settings where biochar application to soils is indicated rather than the full conversion of the biomass to energy and CO₂.

     

New CHP partnerships offering balancing of fluctuating renewable electricity productions

Combined heat and power (CHP) as well as intermittent renewable energy sources (RES) are key elements in future cleaner electricity production systems. This article presents solutions which will integrate fluctuating renewable electricity supplies, such as wind power, into electricity systems using small and medium-sized combined heat and power plants (CHP). Such solutions call for a new organisational setup of partnerships and software tools. The software tools will allow the new partnerships to offer services which are currently only offered by big power plants to electricity markets. The article presents recent results of the development and implementation of such partnerships and focuses on the methodologies and computer tools necessary in order to allow the partnerships to optimise their behaviour on the market. The use of such tools and methodologies makes groups of small CHP plants able to replace large power stations and, at the same time, allows for the integration of a higher share of RES in the electricity supply, resulting in a decrease in both fossil fuels and CO2 emissions.     

Diagnosis and proposals for waste management in industrial areas in the service sector: case study in the metropolitan area of Granada (Spain)

Industrial parks play a significant role in the production and use of goods and services. However, this also means that the environmental problems of each company are concentrated in a relatively small area. One of these problems is solid waste disposal, which has become a critical issue because of its negative impacts as well as the resources consumed. Integrated solid waste management integrates cleaner and more sustainable production strategies by reducing resource consumption and applying mechanisms found in natural ecosystems to industrial systems. Nevertheless, one of the necessary conditions for the design of such a system is a preliminary study of waste generation management in the area. The study presented in this paper characterizes industrial waste production and management in the metropolitan area of Granada (Spain), and analyzes its strengths, weaknesses, opportunities and threats. A similar typology of industrial activities, mainly in the distribution and transportation sector, as well as the proximity of various industrial parks could facilitate their partnership in environmental management. The results obtained in our study point to significant weaknesses in the system, such as the lack of effective waste management tools and training for waste management personnel. Other weaknesses were, the low percentage of selective waste collection and the existence of unauthorized collectors. The paper concludes with specific proposals for waste collection. These recommendations include the creation of the following: (i) a community responsible for waste management; (ii) recycling points in industrial parks; (iii) energy recovery from the waste; (iv) a market to sell, buy, and/or exchange waste; (v) one authorized set of waste management agents that would provide the advantages of an economy of scale.     

Environmental impacts of distributed energy systems—The case of micro cogeneration

Distributed generation in micro cogeneration systems, e.g. reciprocating or Stirling engines and fuel cells, is of increasing interest in the energy market. This paper investigates environmental impacts of micro cogeneration by carrying out a detailed life cycle assessment and an analysis of local air quality impacts of micro cogeneration systems.Most micro cogeneration systems are superior, as far as the reduction of GHG emissions is concerned, not only to average electricity and heat supply, but also to state-of-the art separate production of electricity in gas power plants and heat in condensing boilers. The GHG advantages of micro cogeneration plants are comparable to district heating with CHP. Under the assumption that gas condensing boilers are the competing heat-supply technology, all technologies are within a very narrow range. Looking at the GHG reduction potential on the level of a supply object (e.g. a single-family house) by modeling the operation with a CHP optimization tool, the achievable mitigation potential is somewhat lower, because the micro cogeneration systems do not supply the whole energy demand. Here, fuel cells offer the advantage of a higher power-to-heat ratio.Environmental impacts other than those related to climate and resource protection relate more specifically to technology. In addition to investigating the emissions side, analysis of the air quality situation of a residential area supplied by reciprocating engines was carried out. The analysis shows that for the selected conditions, the additional emission of NO_x due to the engines do not create severe additional environmental impacts.     

Hybrid microalgal biofuel, desalination, and solution mining systems: increased industrial waste energy, carbon, and water use efficiencies

This work reviews retrofitting new waste energy, carbon and water intensive technologies into existing industrial facilities (including electricity generators) to increase net energy, carbon, and water use efficiencies. The three applications reviewed are microalgal ponds consuming flue gasses and providing thermal power station cooling services, thermally driven membrane distillation desalination, and hydrometallurgical solution mining processes to indirectly remove water contaminants, and additional power station cooling. The aim of this work is to explore the unique challenge of site-specificity of retrofitting any or all of the reviewed technologies within existing facilities for commercial operations. The theoretical basis behind higher aggregated efficiencies is essentially vertical integration of infrastructure, energy, and material flows, reducing total costs, net waste, and associated potential environmental contamination. Whilst solution mining and some thermal desalination technologies are not necessarily new in isolation, new technical developments enable these technologies to use waste heat and waste water by operating in parallel with industrial facilities, and effectively subsidise microalgae biofuel water pumping and dewatering. This research determines three fundamental developments are required to enable wide-scale industrial co-located vertical integration efficiencies: (1) fundamental engineering, (2) monitoring system innovation, and (3) technology/knowledge transfer.     

Recent Trends in Residential Energy Use in OECD Countries and their Impact on Carbon Dioxide Emissions: A Comparative Analysis of the Period 1973–1992

In the late 1970s and for most of the 1980s, residential energy use in the OECD underwent significant changes. Many of these changes were a result of more efficient energy use in response to higher energy prices, energy efficiency programs, and the appearance of new technologies for saving energy. This study analyzes these changes and the impact of energy use on carbon emissions in the residential sector for nine OECD countries for the period from 1973 to 1992. The major findings of this analysis are:

1. CO₂ emissions per capita were lower in 1992 in almost all of the countries we studied;
2. The two primary changes were improvements in energy efficiency and a decrease in the share of fossil fuels used for electricity and district heating production;
3. The main source of growth in emissions from residential energy use was increased ownership of electric appliances, where, in spite of important improvements in energy efficiency, ownership grew so rapidly that electricity use (and subsequent emissions) increased;
4. Changes in fuel mix, including both the changes in the share of fuels used in households and the share of fuels used to generate electricity and district heating, led to a decrease in emissions in the nine countries;
5. Increasing the efficiency of electric appliances and further reductions in the intensity of space heating are probably the key elements in a strategy to improve efficiency as a means to lowering CO₂ emissions.

     

以晶体硅太阳能电池产业为例的产业生命周期评价初探

面对日益复杂的环境问题和精细化环境管理需求,为了将生命周期评价在产业结构调整、发展方式转变中更好地发挥作用,对在产业层面开展生命周期评价的方法进行了探索研究.产业生命周期评价是在产品生命周期评价的基础上增加了:①基于“可拆解可组合”生态设计理念的功能单位和系统边界确定;②质量评估和数据整合的数据收集过程;③以不确定性分析来验证数据的合理性.选择晶体硅太阳能电池产业进行了产业生命周期评价的案例应用.结果表明:晶体硅太阳能电池产业可分为4个产品单元和11个工艺单元.基于上述产品单元和工艺单元的资源能源投入和污染物排放数据进行收集,在数据质量评估之后通过数据整合形成了产业生命周期数据清单.产业生命周期环境影响主要集中在呼吸系统影响（41.94%）、化石燃料（25.20%）、致癌（14.89%）和气候变化（8.80%）4个环境影响类别;减少环境影响的精准化途径是减少高纯多晶硅、硅片、电池片产品的电耗,组件产品中焊带消耗,硅片产品中的砂浆消耗和组件产品的铝合金边框消耗.蒙特卡洛分析结果显示,高纯多晶硅生命周期评价结果不确定性较高,与数据质量评估的结果较为一致.案例应用结果说明,产品生命周期评价可将生命周期评价从产品层面提升到产业层面,可为国家产业发展提供科学支撑.      

蒸汽爆破对污泥和餐厨垃圾联合厌氧消化的促进效果

鉴于蒸汽爆破（简称"汽爆"）预处理对污泥和餐厨垃圾联合厌氧消化的影响还鲜有报道,为探讨汽爆预处理对污泥和餐厨垃圾联合中温厌氧消化的促进效果及经济可行性,利用小型发酵罐在35℃下开展了未预处理污泥和餐厨垃圾联合消化、汽爆污泥单独消化、汽爆污泥和餐厨垃圾联合消化的试验,并进行能耗分析.结果表明,未预处理污泥与餐厨垃圾联合消化阶段,VS（挥发性固体）去除率为33.9%,沼气产率为311.0 mL/g（以投料VS计）;汽爆污泥单独消化阶段,VS去除率和沼气产率均略高于未预处理污泥与餐厨垃圾联合消化阶段,但反应器ρ（NH₄+-N）过高,影响产气稳定性,沼气φ（CH₄）较低.汽爆污泥与餐厨垃圾联合消化阶段,VS去除率和沼气产率分别达到49.5%和420.5 mL/g,显著优于未预处理联合消化阶段.能耗分析表明,预处理的升温过程使汽爆预处理整体能耗偏高,但若能有效回收70%的热量,则汽爆预处理可提高污泥-餐厨垃圾联合中温厌氧消化工艺3.34 kW·h/t（以污泥量计）的能量产率.研究显示,汽爆预处理可提高污泥和餐厨垃圾联合中温厌氧消化工艺35.2%的沼气产率,但由于预处理能耗较高,预处理过程中热能的有效回收是汽爆预处理应用于污泥和餐厨垃圾联合中温厌氧消化经济可行的关键.      

基于能值方法的甘薯燃料乙醇产业生态系统分析

发展燃料乙醇已成为替代能源战略下的成熟模式,但传统燃料乙醇生产的污染问题严重影响了燃料乙醇的生存和发展,因此建立以燃料乙醇生产为核心企业,包括由原料种植者、乙醇生产者、分解者、资源回收利用者等一系列利益相关者组成的产业生态系统,已成为燃料乙醇可持续发展的有效途径. 根据燃料乙醇生产过程中对废物处理和资源化利用情况,将其划分成传统生产方案(方案Ⅰ)、废物处理生产方案(方案Ⅱ)和产业生态系统方案(方案Ⅲ),并采用改进后的能值分析方法及指标体系对3种生产方案进行比较分析. 结果表明:与方案Ⅰ相比,通过废物处理和中水回用,方案Ⅱ的ε_EYR(能值产出率)提高了59.37%,ε_ELR(环境负荷率)降低了75.39%;延长产业链,增加循环利用方式后,方案Ⅲ比方案Ⅰ的ε_EYR提高了86.19%,ε_ELR降低了82.98%. 3种生产方案的可持续发展能力为方案Ⅰ<方案Ⅱ<方案Ⅲ.      

Modern Biomass Conversion Technologies

This article gives an overview of the state-of-the-art of key biomass conversion technologies currently deployed and technologies that may play a key role in the future, including possible linkage to CO₂ capture and sequestration technology (CCS). In doing so, special attention is paid to production of biofuels for the transport sector, because this is likely to become the key emerging market for large-scale sustainable biomass use. Although the actual role of bio-energy will depend on its competitiveness with fossil fuels and on agricultural policies worldwide, it seems realistic to expect that the current contribution of bio-energy of 40–55 EJ per year will increase considerably. A range from 200 to 300 EJ may be observed looking well into this century, making biomass a more important energy supply option than mineral oil today. A key issue for bio-energy is that its use should be modernized to fit into a sustainable development path. Especially promising are the production of electricity via advanced conversion concepts (i.e. gasification and state-of-the-art combustion and co-firing) and modern biomass derived fuels like methanol, hydrogen and ethanol from ligno-cellulosic biomass, which can reach competitive cost levels within 1–2 decades (partly depending on price developments with petroleum). Sugar cane based ethanol production already provides a competitive biofuel production system in tropical regions and further improvements are possible. Flexible energy systems, in which biomass and fossil fuels can be used in combination, could be the backbone for a low risk, low cost and low carbon emission energy supply system for large scale supply of fuels and power and providing a framework for the evolution of large scale biomass raw material supply systems. The gasification route offers special possibilities to combine this with low cost CO₂ capture (and storage), resulting in concepts that are both flexible with respect to primary fuel input as well as product mix and with the possibility of achieving zero or even negative carbon emissions. Prolonged RD&D efforts and biomass market development, consistent policy support and international collaboration are essential to achieve this.     

啤酒的生命周期评价

本文在啤酒酿造阶段基础上,将原料种植及麦芽制备引入研究范围,利用Gabi5.0软件对啤酒进行从摇篮到大门的生命周期评价.各阶段考虑温室效应、酸化、富营养化、非生物资源消耗、人体潜在毒性、光化学毒性6种环境影响类型.结果表明,温室效应是啤酒生产对环境影响的主要类型,占总环境影响潜值43.75%,环境影响由强至弱分别为温室效应、富营养化、酸化、人体潜在毒性、光化学毒性和非生物资源消耗.灌装阶段是造成环境影响的主要阶段,占总环境影响潜值39.77%,种植阶段次之.其中灌装阶段的温室效应、非生物资源消耗、人体潜在毒性和光化学毒性影响潜值为啤酒生产各阶段最高值,种植阶段的富营养化、酸化影响潜值在各阶段最高.对灌装阶段采用传输管道改进,空压机热能回收、蒸汽二次利用等清洁生产方案降低能源消耗和环境影响,方案实施后蒸气和电能消耗分别减少247.66 MJ和4.46 k Wh,温室效应影响潜值减少19.18%,具有一定的环境效益和经济效益.     

Integrated assessment of CCS in the German power plant sector with special emphasis on the competition with renewable energy technologies

The study presents the results of an integrated assessment of carbon capture and storage (CCS) in the power plant sector in Germany, with special emphasis on the competition with renewable energy technologies. Assessment dimensions comprise technical, economic and environmental aspects, long-term scenario analysis, the role of stakeholders and public acceptance and regulatory issues. The results lead to the overall conclusion that there might not necessarily be a need to focus additionally on CCS in the power plant sector. Even in case of ambitious climate protection targets, current energy policy priorities (expansion of renewable energies and combined heat and power plants as well as enhanced energy productivity) result in a limited demand for CCS. In case that the large energy saving potential aimed for can only partly be implemented, the rising gap in CO₂ reduction could only be closed by setting up a CCS-maximum strategy. In this case, up to 22% (41 GW) of the totally installed load in 2050 could be based on CCS. Assuming a more realistic scenario variant applying CCS to only 20 GW or lower would not be sufficient to reach the envisaged climate targets in the electricity sector. Furthermore, the growing public opposition against CO₂ storage projects appears as a key barrier, supplemented by major uncertainties concerning the estimation of storage potentials, the long-term cost development as well as the environmental burdens which abound when applying a life-cycle approach. However, recently, alternative applications are being increasingly considered?Cthat is the capture of CO₂ at industrial point sources and biomass based energy production (electricity, heat and fuels) where assessment studies for exploring the potentials, limits and requirements for commercial use are missing so far. Globally, CCS at power plants might be an important climate protection technology: coal-consuming countries such as China and India are increasingly moving centre stage into the debate. Here, similar investigations on the development and the integration of both, CCS and renewable energies, into the individual energy system structures of such countries would be reasonable.     

Environmental and economic assessment of a greenhouse waste heat exchange

As the economic costs of energy and the negative externalities associated with the combustion of fossil fuels threaten the economic viability of greenhouses in northern climates there is a renewed interest in the use of waste heat. This paper presents a technical and economic methodology to determine the viability of establishing waste heat greenhouses using the waste heat from industrial processes in northern climates. A case study is presented of an exchange between a tomato greenhouse and a flat glass manufacturing plant, which found the waste heat system is significantly more economic to operate than a purely natural gas system.     

关于有机废物类生物质能历史定位及其能源价值评估指标探讨

中国是煤炭消耗的第一大国,同时又是有机废物生物质贮存量第一大国。本文叙述了全球生物质能的历史定位,生物质能的主要评价指标,生物质的能源转换技术和生物质能可供给量模型分析与预测实例,以及我国有机废物类生物质能源化利用途径,并探讨了有机废物的能源利用与废物污染防治相结合的生物质能源发展道路。     

江苏省电力发展与环境变化的灰色关联分析研究

文章以灰色关联分析的理论与方法为基础,分别将江苏全省SO2排放量、工业烟（粉）尘排放量、工业废气排放量和工业固体物产生量作为因变量参考数列,江苏省地区生产总值、发电总量、火力发电量、火力发电量占发电总量比重作为比较数列,对电力发展与环境变化进行综合分析,结果表明火力发电对环境变化影响较大.因此,积极发展新能源发电项目,扩大新能源发电比重,降低火力发电比重,构建合理的能源结构成为江苏省环境保护的重中之重.     

Life cycle assessment of MSW-to-energy schemes in Thailand

Life cycle assessment was performed to evaluate environmental impacts of two municipal solid waste (MSW) to energy schemes currently practiced in Thailand: incineration and anaerobic digestion. Potential impacts such as global warming, acidification, stratospheric ozone depletion, and photo-oxidant formation were avoided due to net electricity production and also fertilizer production as by-products from the anaerobic digestion scheme. In addition, the anaerobic digestion resulted in the higher net energy output compared to the incineration scheme. However, the incineration had less potential impact for nutrient enrichment. The LCA results were also useful in determining where the improvements could be made for both the schemes. In order to adopt a sustainable waste management system elsewhere in the country, decision makers may need to consider a combination of techniques, or an integrated method of management. LCA could serve as an invaluable tool for such an analysis.     

Cleaner production alternatives: Biomass utilisation options

The increasing price of energy, the security of supply, the reduction of green house gases, and the scarcity of oil and gas urge the use of more and more renewable energy. An important renewable energy source is the biomass which can be applied for heat, electricity, and transportation fuel production. The heat and electricity production are the so called “direct utilisation” alternatives and the transportation fuel production alternatives are the “indirect utilisation” alternatives of biomass energy. If efficient land use is considered, the alternatives can be compared on the basis of the utilisable energy produced from the biomass per hectare. It is shown that the bioethanol production from corn has about 89–99% less energy production capability than that of the direct utilisation alternatives. The cellulosic type bioethanol production technologies, since these partially directly utilise the biomass energy, have better energy utilisation potential, that is about 40–50% of direct alternatives.     

同安区工业固体废物管理现状及防治对策

阐述了厦门市同安区工业固体废物的环境管理现状，分析其原因，并就辖区工业固废污染防治工作提出了对策措施。     

Eco-efficiency evaluation of iron rod industry in Nepal

This paper presents the eco-efficiency of energy intensity, material consumption, water use, waste generation, and CO₂ emission in terms of production value in net sales (US$) per environmental influence using empirical evaluation. Evaluation has been considered only within production process boundary of iron rod industry. Evaluation of eco-efficiency tried to couple the economic and environmental influences of industry to know economic and environmental excellence. Eco-efficiency of iron rod industry was quantitatively analyzed and determined that energy, material consumption, water use, waste generation, and CO₂ emission eco-efficiency have been increased gradually along with increased production during analysis period of five years (2001–2005). It was possible due to installing heat recovery unit along with innovative processes modification. While comparing each year's eco-efficiency of all above-mentioned parameters, eco-efficiencies were increased that indicates less resource use and less waste released. As a general statement of overall comparison and characterization of eco-efficiencies of five years duration, iron rod industry was eco-efficient in all aspects. Eco-efficiency being an emerging trend has not yet been implemented in Nepal. It is further recommended to adopt the eco-efficiency evaluation in other industries. In addition, it is high time to augment the provision of eco-efficiency concepts in industrial policy and legislation concerned.